Device for turning a nut means on a screw bolt

Abstract

An improved device for turning a nut means on a screw bolt arranged on a bolthole circle wherein the device includes: a support ring having recesses for receiving the bolt and the nut means; a turning unit fastened to the ring for imparting rotary motion to the nut means; and a transport safety means for engaging and retaining the nut means when it reaches its unscrewed end position. In accordance with the invention, the improvement comprises employing a nut means having a threaded portion for engaging the transport safety means and including in the latter means a member attached to the support ring and in surrounding relationship to the bolt, the latter member having a counterthread and being positioned so that the threaded portion of the nut means is engaged by the counterthread before the nut means reaches its end position.

What is claimed is: 
     
       1. In combination: a nut;   a lug assembled to the nut for driving it;   means for rotating the lug and driving the nut onto or off of, a screw bolt;   means for supporting the rotating means having an opening for passage of the screw bolt and the assembled lug and nut;   means including a counterthread connected to the support means for engaging the assembled lug and nut when the nut nears an end position and for retaining them when the nut is unscrewed from the bolt; and   a threaded portion on the assembled lug and nut for engaging the counterthread.   
     
     
       2. The combination of claim 1 in which the threaded portion is on the lug. 
     
     
       3. The combination of claim 2 in which the threaded portion is on the external surface of the lug. 
     
     
       4. The combination of claim 1 in which the threaded portion engages the counterthread while the nut is on the bolt thread.